JPS5978222A - Room temperature-curable elastic composition - Google Patents

Abstract

PURPOSE:To titled moisture-curable resin composition excellen in weather resistance, heat resistance, and durability, comprising an acrylate ester monomer, a bifunctional radical-polymerizable compound, and a mercaptoalkoxysilane compound. CONSTITUTION:A moisture-curable copolymer composition (room temperature- curable elastic composition, preferably, of an average MW of about 3,000-10X 10<4>) is prepared by copolymerizing (A) an acrylate ester monomer of formula I (wherein R1 is a 2-8C alkyl), e.g., ethyl acrylate, with (B) a bifunctional radical- polymerizable compound (e.g., polyoxyalkylene glycol diacrylate) in the presence of (C) about 0.002-0.1mol, per mol of component A, of a mercaptoalkoxysilane of formula II (wherein R2 is a bivalent hydrocarbon group, R3 is a 1-4C alkyl, X is methoxy or ethoxy, and a is 0, 1, or 2), e.g., gamma-mercaptopropyl-methyldimethyoxysilane, preferably component B being used in an amount about 2-6 molar times that of component C.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a room temperature curable elastic composition, more specifically a needle base,
This invention relates to a moisture or moisture-curable copolymer composition that is suitable for use as an inexpensive elastic sealing material that has excellent weather resistance, heat resistance, and durability.

Elastic sealants are indispensable materials in various industries such as architecture, civil engineering, vehicles, and electrical equipment, and their usage is increasing year by year.

Currently, polyurethane is used as an elastic sealant.

Various polymer compositions such as polyacrylic emulsion type, modified silicone type, polysulfide type, and silicone type are used. Among these, silicones, especially two-component silicones, have superior properties in terms of needle base, weather resistance, heat resistance, and durability compared to other θ polymer compositions, and are therefore particularly useful as architectural sealants. However, the contamination rate is high, and the contamination of the construction surrounding parts, which is thought to be caused by the migration of low molecular weight polydimethylsiloxane in the composition, and the adhesion with the coating film applied to the surface of the elastic sealant. There's a problem.

Therefore, as a result of intensive research in order to obtain an excellent material for sealing materials that solves these various problems in the various sealing materials mentioned above, the present inventors discovered that a specific acrylic acid ester monomer and a specific bifunctional radical The present invention was completed based on the discovery that a polymer containing an alkoxysilyl group obtained by polymerizing at least one type of mercaptoalkoxysilane with at least one type of mercaptoalkoxysilane has the desired properties as a sealing material. I ended up doing it.

That is, the present invention.

(a) Formula % Formula %) [In the formula, Rt is an alkyl group having 2 to 8 carbon atoms] One or more acrylic acid ester monomers - (b) Radical polymerization of two in one molecule one or more bifunctional radically polymerizable compounds having a functional group, and (C) formula % formula %) [:) [wherein, R2 is a divalent hydrocarbon group, R8 is a carbon number 1 to 4
, X is a methoxy group or ethoxy group, 1 is Oll or 2]. It's about doing.

This is component (a) used in the present invention.

Examples of the 7-acrylic acid ester monomer represented by the formula CH2=CHC0OR1 [l::) [in the formula, R1 is an alkyl group having 2 to 8 carbon atoms] include Eva, ethyl acrylate, propyl acrylate, n-butyl Acrylate, inbutyl acrylate, amyl acrylate, hequinyl acrylate, 2-ethylhexyl acrylate,
Preferred are straight-chain, branched-chain and alicyclic argylene ethers having 2 to 8 carbon atoms, such as cyclohexyl acrylate and n-octyl acrylate. If the number of carbon atoms is 1, the physical properties of the resulting copolymer will be hard and brittle, and if the number of carbon atoms is 9 or more, the resulting copolymer 01 will not only have low strength but also tend to develop stickiness, which is undesirable.

Instead of the above-mentioned acrylic ester monomer, it is also possible to use a methacrylic acid ester monomer.

If this type of acrylic acid ester monomer is used, the resulting composition may not have rubber elasticity, which is not preferable. However, other monomers that can be polymerized with the acrylic ester may be used in combination within a range that does not impair the physical properties required for the final composition, usually at a ratio of 20 to 50 or less. Examples of such monomers include -Methacrylic acid enteles (methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, inbutyl methacrylate-2-ethylhexyl methacrylate, lauryl methacrylate, tridecyl methacrylate, benzyl methacrylate-cyclohexyl methacrylate, tetrahydrofurfuryl methacrylate-2 ~Hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, glycidyl methacrylate, 2-methoxyethyl methacrylate, 2-ethoxyethyl methacrylate, etc.), the above formula (
Acrylic acid enteles other than I) (methyl acrylate, glycidyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyla/71J rate, etc.), methacrylic acid, vinyl acrylate-101tau acid, 70
Vinyl lobuonate, vinyl persaccharide (trade name Beoba, manufactured by Shell Chemical), vinyl chloride-acrylonitrile, nutylene, acrylamide, N-methylolacrylamide, vinylpyridine, maleic anhydride-vinylpyrrolidone, butadiene, etc. can be mentioned.

The bifunctional radical M compound which is the component (13) used in the invention has two silane polymerizable groups in one molecule, such as vinyl group, acryloxy group, methacryloxy group - allyl group, etc. Diacrylates of low molecular weight glycols such as ethylene glycol, propylene glycol, butanediol, and hegysandiol θ; Oxypropylene glycol, polyoxytetramethylene glycol, 'J (1) Di(meth)acrylates of polyoxyalkylene glycols; 2
Salts, condensates of type 1 and excess υnobricols, or cy(meth)acrylates of polyester diols such as polyε-caprolactone diol; Molecules obtained from excess amount of polyoxyalkylene glycol-polyester diol and diincyanate compounds Di(meth)acrylates of urethane prepolymers having a hydroxyl group at the m-terminus; polyoxyalkylene glycol, polyether diolt, etc. Obtained from an excess amount of a diisocyanate compound; Di(meth)ac+)v- obtained by reacting a Cmeth)ethyl acrylate compound containing
a; Di(meth)acrylates obtained by the reaction of a C meth)ethyl acrylate compound having a hydroxyl group and a diisocyanate compound; Obtained by the reaction of a mono(meth)acrylate of polyoxyalkylene glycol or polyester diol and a diisocyanate compound Di(meth)acrylates Di(meth)acrylates are obtained from hydroxyl group-containing polylactone mono(meth)acrylate and diisocyanate compound obtained by polymerizing lactones on the hydroxyl groups of di(meth)acrylate ethyl compounds having hydroxyl groups. ) Acrylates; 2 in 1 molecule
Di(meth)acrylates obtained from glycidyl(meth)acrylate and compounds with active hydrogen based on amino or imino groups; divinylbenzene;
Examples include allyl (meth)acrylate; vinyl (meth)acrylate; divinyl adipate; divinyl sebacate; diallyl phthalate, and the like.

In addition to the above 1.2-functional radically polymerizable compound, if desired for the purpose of adjusting physical properties, etc., the following formula % formula %)) :] [In the formula, R4 is the number of carbon atoms] ~ 4 alkyl group , ■ is a methoxy group or an ethoxy group, and 1) is O-1 or 2.
) [: [In the formula, I branch 5 is hydrogen or methyl group, R6 is divalent F
A hydrogen hydride x, R7 is carbon number] -4 argyl Z is also a methoxy group or ethoxy li, 1] is 0. 1 or 2
] One or more selected from acryloxyalkoxysilanes and metaacryloxyalkoxysilanes shown in
The 2'q ability radial force. It is also possible to carry out copolymerization in an equimolar amount or less with respect to the compound to be synthesized.

Such alkoxysilanes include vinyltrimethoxysilane-vinylmethyldimethoxysilane, vinyldimethylmethoxysilane, vinyltriethoxysilane,
Vinylmethyljethoxysilane, γ-C meta)acryloxypropyltrimethoxysilane, γ-[meth]acryloxypropylmethyldimethoxysilane, γ-(meth)
Examples include acryloxypropyltriethoxysilane and γ-(meth)acryloxypropylmethyljethoxysilane.

(Formula, which is the component (C) used in the present invention)
4 alkyl group, X is methoxy group or ethoxy group, 3
is 0.1 or 2] Mercaptoalkoxysilane adjusts the average molecular weight of the resulting polymer and at the same time
-It is used to introduce a cycilyl group, and the blending amount is adjusted as appropriate depending on the use of the resulting polymer.

The polymer which is the main component of the room temperature curable composition according to the present invention is produced by radical copolymerization of the above components (a) and (b) in the presence of the above component (C).

As a radical polymerization initiator, for example, α,α1-azobisinbutyronitrile (AIBN) + α,α1-azobisinvaleronitrile, σ,α1-azobis-2,4
Known polymerization methods using - dimethylvaleronitrile - benzoyl peroxide - methyl ethyl ketone peroxy F etc. - techniques such as bulk type coalescence solution polymerization may be used;
Further, redox polymerization may be performed by combining a redox catalyst such as a transition metal salt, an amine, etc. and a peroxide-based radical polymerization initiator.

Since the resulting polymer has room temperature curability, it is useful as a material for sealants, paints, and adhesives. especially,
When used as a sealant material, usually (a
) Acrylic acid ester monomer [I] (If using other polymerizable monomers, include them) per mole (C)
chain transfer agent having a mercapto group 0.002 to 0.1,
In particular, 0.004 to 0.06 mol is used, and component (C) 1
It is preferable to use 0.2 to 1.0 moles of the bifunctional radically polymerizable compound as component (b) per mole.

The sealant composition includes the polymer of the present invention, a plasticizer, a filler, a reinforcing agent, an anti-sagging agent, a coloring agent,
Physical property modifiers, stabilizers, adhesion promoters - curing accelerators, solvents, etc. can be blended, but there is no need to use anti-aging agents, which are required with conventional elastic sealants (polyurethane-based, modified noricone-based, etc.). It is extremely useful because it has an excellent needle point, weather resistance, heat resistance, and durability.

As a plasticizer, for the purpose of controlling physical properties and properties, phthalic acid enethers such as cyphytyl phthalate, dihebutyl phthalate di[2-ethylhexyl) phthalate, butyl benzyl phthalate, and butyl phthalyl butyl glycolate; dioctyl Non-aromatic dibasic acid enteles such as adipate and dioctyl sebacate; esters of polyalkylene glycols such as diethylene glycol dibenzoate and triethylene glycol dibenzoate; phosphoric acid esters such as tricresyl phosphate and tributyl fonupate; Chlorinated halaf (: [i) Aromatic hydrocarbon oils such as fulkyldiphenyl and partially hydrogenated terphenyl can be used alone or in combination of two or more, but are not necessarily required.
These plasticizers can also be blended during polymer production.

Fillers and reinforcing materials are used for the purpose of improving the physical properties (elongation, tensile strength, etc.) of the curable composition, adjusting the properties, and reducing contamination. Calcium carbonate surface-treated with surfactant, anionic surfactant, etc.; Magnesium acetate; Talc; Titanium oxide; Barium sulfate; Alumina; Metal powders such as aluminum, zinc, iron, etc.; Bentonite; Kaolin clay; Fumed silica; One or more of ordinary materials such as quartz powder, carbon black, and talc are used.

In particular, when the composition of the present invention is used, the needle tip has excellent weather resistance, so even if fillers and reinforcing materials that provide transparency, such as fumed silicone strength, are used, the needle tip and weather resistance can be sufficiently used outdoors. Give sex.

Examples of anti-sagging agents include hydrogenated castor oil and its derivatives: metal soaps such as calcium nutearate, aluminum stearate, and barium nutearate. It may be unnecessary depending on the situation.

As the coloring agent, ordinary inorganic or organic pigments, dyes, etc. can be used as required. The polymer according to the present invention is almost colorless and has excellent color fastness, so if the weather resistance of the pigments and dyes used is taken into consideration, excellent color tone can be maintained for a long time.

As a physical property modifier, various silane coupling agents such as -methyltrimethoxysilane, dimethyldimethoxysilane-trimethylmethoxysilane, argylalkoxysilanes such as n,-furobyltrimethoxysilane; dimethyldiisoprobenoxysilane , methyltriinpropenoxysilane, γ-glycidoxypropylmethyldiimbropenoxysilane, and other alkylisopropenoxysilanes; γ-glycidoxypropylmethyldimethoxysilane, r-glycidoxypropyltrimethoxy silane,
Vinyltrimethoxysilane, vinyldimethylmethoxysilane, γ-aminopropyltrimethoxysilane, N-(
β-aminoethyl)aminopropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane-γ
An alkoxysilane having a functional group such as -mercaptoderopylmethyldimethoxysilane is added as necessary.

M 7 alkoxysilanes tend to become harder as the number of alkoxy groups bonded to silicon atoms increases. Usually, the physical property modifier is a polymer 10 used as a material for sealing materials.
Approximately 5 parts or less relative to 0 parts will exhibit sufficient effects.

As stabilizers, lower alcohols such as methanol and ethanol, and various alkoxysilane-based silane coupling agents can be added to 100 parts of the polymer, although they are not necessarily required as long as water is removed from the curable composition. 10 in line
may be used below.

As for the adhesion promoter, the polymer of the present invention itself has adhesion properties to galanus, other ceramics, metals, etc., and can be bonded to a wide range of materials by using various types of brimers. Therefore, although it is not necessary, it is possible to improve adhesion to a wider variety of adherends by using one or more of various silane coupling agents, algylticnates, aromatic polyincyanates, etc. can do.

As curing accelerators, te) ethyl titanates such as 5-butyl titanate and tetrapropyl titanate; organic tin compounds such as dibutyltin dilaurate, dibutyltin maleate, dibutyltin diacetate, tin octylate, and silver naphthenate; octylic acid; Lead; butylamine, octylamine,
Dibutylamine, monoethanolamine, jetanolamine, triethanolamine, diethylenetriamine, treethylenetetramine, oleylamine'-octylamine, cyclohexylamine, benzylamine, diethylaminoprobylamine, xylenediamine, triethylenediamine, guanidine, diphenylguanidine, 2,4.6-) Linu(dimethylaminomethyl)phenol, morph]nilin, N-methylformoline, 1
,3-diazabicyclo(5,4゜6)undecene-7(
σ-noamine compounds such as DBUl or these (/,
) h/salts such as levonic acids; low molecular weight 71 solamide resin obtained from excess polyamine and polybasic acid; 1 reaction product of excess polyamine and epoxy compound; 1 silane cup having amino groups; Aminoprobilt 1 nomethoxysilane, N-(β-aminoethyl)
Amitafu 0 Flobil Methyl Dimethokifu 9 Fu, etc. 0] 1, 4 or 2 or more types can be removed as needed (,N.

Note that solvents may be added for the purpose of improving workability, reducing viscosity θ, etc. For example, aromatic hydrocarbon series solvents such as toluene and xylene, ethyl acetate, butyl acetate,
0-ester solvents such as amyl acetate and seronyl acetate,
Ketone solvents such as methyl ethyl ketone, methyl isophyl ketone, diisobutyl ketone, etc. are listed. This solvent may be used during polymer production.

It is not particularly necessary to add an anti-aging agent.

Ordinary antioxidants and ultraviolet absorbers may be used.

Such a sealing composition can be prepared as a one-component type in which all the ingredients are stored in advance and cured by the moisture in the air after application, or it can be prepared separately as a curing agent - a curing catalyst, It can also be prepared as a two-component type, in which components such as fillers, plasticizers, water, etc. are blended in advance, and the polymer composition is mixed with a main ingredient containing the above-mentioned compounding agent C) before use.

In the case of one-component type, all the ingredients are mixed in advance, so
It is preferable that a compounding agent (material) containing water is dehydrated and dried before use, or dehydrated during compounding and kneading by reducing pressure or the like.

In the case of two-component type: Since there is no need to blend a curing catalyst into the main component containing a polymer, there is little concern about gelation even if Compound C material contains a small amount of water, but When storage stability is required, dehydration and drying is preferred.

As the dehydration/drying method, suitable methods include heat drying for solid materials such as powder, and vacuum dehydration method for liquid materials, or dehydration methods using synthetic zeolite, activated alumina, silica gel, etc. Alternatively, dehydration may be carried out by blending a small amount of an incyanate compound and causing the incyanate group to react with water. In addition to such dehydration drying methods, lower alcohols such as methanol and ethanol, alkoxysilane compounds such as n-propyltrimethoxysilane-vinylmethyldimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, r-glycidoxypropyltrimethoxysilane, etc. By adding , storage stability is further improved.

Hereinafter, the present invention will be explained in more detail based on Examples.

Example 1 (a) n-butyl acrylate 1289 (1 mol)
, tetraethylene glycol cyacrylate 1°16g
(0,00375 mol), γ-mercaptopropylmethyldimethoxysilane 1.35 g (0,0075 mol) Oyobi di(2-ethylhexyl) phthalate 32//, α, α1-azobinuin butyroni) IJ le 0.
Add 3g and stir to dissolve. The mixed solution 3 (1) was placed in a 300 ml separable flanco equipped with a stirrer and replaced with dry nitrogen gas, and gradually heated in an oil bath (80° C.) while passing nitrogen gas.

After a few minutes, polymerization begins and heat is generated, so check that the heat generation slows down and the viscosity increases (0), then continue stirring and heating, and after about 10 minutes, gradually drop the remaining mixed liquid using the dropping funnel. and polymerize. After dropping the entire amount in about 3 hours, about 30
Heating was continued for 1 minute, then 0.19 g of α,α1-azobinisobutyronitrile was added, and heating and stirring was continued for about 1 hour to complete the polymerization reaction. The resulting polymer is a colorless and transparent viscous liquid, with a viscosity of 870 voids at 20°C.
The polymerization rate was found to be 99.5 as determined by the reduced pressure change method (non-volatile fraction method) at 10° C. for 3 hours.

(b) Add rutile-type titanium white to 100 g of this polymer.

g, fatty acid surface treatment method calcium acid 90p, toluene 1
After pre-mixing 2 g of OF-methanol, it was kneaded uniformly using three rolls, and then decompressed for 5 minutes in a vacuum mixer.
A white paint-like non-sagging composition is obtained.

Add 0.2 g of dibutyltin dilaurate and 0.4 g of n-octylamine to the entire amount of this white paint-like composition, mix well under reduced pressure to avoid air bubbles, and then form a sheet of about 2.5πm thick on a polyethylene plate. Stretch to 20℃65
%RI-I room for 7 days, a cured sheet exhibiting rubber-like elasticity was obtained.

(C) Rubber physical properties of this cured sheet were determined by JISK-(3)
When a No. 3 dumbbell specified in 301 was measured using an Autograph DO5-5000 manufactured by Shimabara Seisakusho at a tensile rate of <500ffπ/min as specified in JISK-6301, the elongation rate was 500% and the cutting strength was 4°3kqE10n.
Show me.

Example 2 128 g (1 mol) of n-butyl acrylate, 0.99 g (0,005 mol) of divinyl adipate, 1.80 f/gamma-mercaptopropylmethyldimethoxysilane
(0.01 mol) and 32 g of di(2-ethylhexyl) phthalate, polymerization was carried out in the same manner as IIJI (a).
Polymerization rate 9 by 0°C 3 hours vacuum decompression change method (non-volatile method)
A 9% colorless, transparent, viscous polymer was obtained.

When a cured sheet was produced using this polymer in exactly the same manner as in Example (b), a cured sheet exhibiting rubber-like elasticity was obtained. Use this cured sheet.

When the physical properties of the rubber were measured in exactly the same manner as in Example 1 (C), the elongation rate was 380% and the cutting strength was 8.31 cqf/a.
showed n2.

Patent applicant: Sunstar Giken Co., Ltd. Agent 9F Physician Aoyama 7.1 person

Claims (5)

[Claims] (1) (a) Formula % Formula % [In the formula, R1 is an alkyl group having a prime number of 2 to 8] One or more acrylic ester monomers, (b) 2 radicals in one molecule One or more bifunctional radically polymerizable compounds having a polymerizable group, and 0 formula%) [wherein, R2 is a divalent hydrocarbon group, and R8 is a carbon number of 1 to 4]
, X is a methoxy group or ethoxy group, and 3 is 0.1 or 2]. thing. (2) The above mercaptoalkoxysilane (C) 0.002 to 0 per mole of acrylate monomer (a)
．． Composition according to paragraph (1), using 1 mol. (3) Add 0.2 of the bifunctional radical polymer compound (b) to 1 mole of the mercaptoalkoxysilane (c).
The composition according to paragraph (1) in which ~1.0 mol is used. (4) Any of the items (1) to (3), in which, in addition to the acrylic acid ester monomer (a), a polymerizable monomer that can be copolymerized with the monomer is used in an amount of 20 to qO molt. The composition according to any one of the above. (5) Formula (41% formula%) [In the formula, R4 is an alkyl group having 1 to 4 carbon atoms, Y is a methoxy group or a toxy group, and b is 0.1 or 2] Vinyl alkoxysilane represented by and the formula [wherein, R
5 is hydrogen or a methyl group - R6 is a divalent hydrocarbon group, R
7 is an alkyl group having 1 to 4 carbon atoms, Z is a methoxy group or an ethoxy group, and b is 0.1 or 2. One or more selected acryloxyalkoxysilanes or methacryloxyalkoxysilanes represented by
The composition according to any one of items (1) to (4), which is used in combination in an equimolar amount or less with respect to the bifunctional radically polymerizable compound.